US Army chief spokesman, Brigadier General Mark Kimmitt, on Monday called Aljazeera, and other Arab media outlets the "anti-coalition media" and advised viewers to "change the channel".
Meanwhile, General John Abizaid, the head of US Central Command, singled out Aljazeera as portraying US military action "as purposely targeting civilians, and we absolutely do not do that, and I think everybody knows that."
"They have not been truthful in their reporting. Haven't been accurate," said Abizaid.
Aljazeera denied the allegations. "Aljazeera rejects these accusations and consider them a threat to the right and the mission of the media outlets to cover the reality of what is happening in Iraq during this tough and complicated field circumstances," said Aljazeera in a statement on Tuesday.
"This is an unjustified pressure against the freedom of the press," added the statement.
Aljazeera has also pointed out that it will continue to cover the events in Iraq and present all the points of view on Iraq "objectively, independently and professionally".
Aljazeera reiterated its standing with its editorial policy "that is commited to portraying different opinions and presenting the viewers with a full and real picture."
US General John Abizaid lashed
out at Aljazeera TV
US Marines, responding to the murder of four American guards in Falluja on 31 March, attacked resistance fighters in the town last week.
As fighting intensified, US authorities have stepped up a separate battle for public opinion, tightly controlling the flow of information to journalists whose ability to move freely in Iraq has been limited by increasing danger.
Doctors in Falluja say more than 700 people have died in the fighting. The US military says they are mainly "rebels", but Aljazeera, with teams inside the town, insists a large number of women and children are among the dead.